1. Field of Invention
This invention relates to a map display device and a recording medium of a vehicle navigation system which searches for a route from a departing point or a present position to a destination, and executes route guidance in accordance with the searched route.
2. Description of Related Art
There are various types of vehicle navigation systems for providing a driver with guidance information along a vehicle travel route, such as a navigation system that searches for a route to a destination and provides visual/audio guidance on characteristic information relating to a map and route information to the destination, and a navigation system that displays a map centering the present position and providing information about the vicinity of the present position, etc. For example, regarding a vehicle navigation system having functions, such as route search and route guidance, there are proposed systems, such as a system for simultaneously providing the positional relationship between the destination and the present position and the detailed information on the vicinity of the present position of the vehicle, by displaying a wide-area map including the area from the present position to the destination and the detailed map of the present position on the two-part split screen (e.g. Japanese Patent Publication No. 335390/92), a system for identifying the relative position in the wide-area map by displaying a scaled-down map on a sub-window through the use of a main window and a sub-window (e.g. Japanese Patent Publication No. 270172/95), and a system for displaying a window frame matching the enlarged scale on the map and then magnifying a road map within the frame when the system displays a magnified map (Japanese Patent Publication No. 20259/96).
According to the above-mentioned system which displays a wide-area map and a detailed map on the two-part split screen, the system fixes the wide-area map screen and alters the position and the direction of the present position mark, whereas, regarding the detailed map screen, the system fixes the display position of the present position mark in the center of the map and then scrolls the map. Therefore, the above-mentioned system makes it difficult for the driver to identify which display area of the wide-area map corresponds to the continuous variable display area of the detailed map. Regarding the system displaying a sub-window, the sub-window superimposed on the main window makes the driver difficult to see because a part of the map displayed on the main window is covered by the sub-window. Regarding the system displaying a window frame for displaying a magnified map on the un-magnified map, since the wide-area map is erased after being magnified, its relative position in the wide area cannot be identified.